Pressure groups of Tory politicians and activists are multiplying. Conservative Voice, launched in September to champion traditional policies on crime, immigration and jobs, now claims thousands of supporters. Bright Blue campaigns for “progressive conservatism” and pushes causes such as environmentalism and international development. MPs representing marginal constituencies last year formed The Forty to devise strategies for the 2015 election. And so on…

Five strains of thought can be detected. First come the two, subtly different, varieties of David Cameron’s “modernising” project, which seeks to anchor the party in the electorally decisive centre ground…

Three other strains are less influential. The pitiful remnants of the party’s once-strong left wing, economically interventionist and relaxed about Europe, huddle around the Tory Reform Group. Better represented among the party grassroots are the social conservatives and the libertarians…

The Tory tribes are particularly vivid and noisy these days. Public disagreement between Conservatives and Liberal Democrats at the heart of the coalition government, as well as a widespread belief among Tory MPs that Lib Dems are steering the ship, has made dissent seem more acceptable…

The broadly loyal culture of the party means its tribes are not nearly as dangerous as they might seem. Whereas Labour periodically breaks into warring dogmatic factions, Conservatives are generally united by a broad set of common principles—including a sceptical attitude to grand political schemes…